United Kingdom

LINX London Internet Exchange
UK based nonprofit exchange, used largely between ISPs.
http://www.linx.net/

LIPEX - London Internet Providers Exchange
Started in October of 2001 as an alternative peering point in London, UK.
http://www.lipex.net/

London Network access Point - LoNaP
Internet exchange in the London docklands area with rules and regulations, background statistics with a looking glass interface.
http://www.lonap.net/

Manchester Network Access Point - MaNAP
Overview with presentation, rules and regulation. [Flash]
http://www.manap.net/

rbiex.net
Nonprofit alternative exchange a good starting point for smaller ISPs, based in Docklands, London.
http://www.rbiex.net

XchangePoint Europe
Commercial Internet Exchange Services in London, UK, and Hamburg, Germany.
http://www.xchangepoint.net/